1. Field of the Invention
The present invention relates to an optical connector plug with a shutter represented by an LC-type plug used for a connecting end of an optical fiber cable.
2. Prior Art
In the prior art, an optical connector plug with a shutter illustrated in FIG. 7A to FIG. 11C, for example, an LC type plug 15 with a shutter described as a representative example includes: a cylindrical plug frame 18 having a ferrule 16 and a resilient member 17 configured to bias the ferrule 16 forward in the interior thereof; a cylindrical front housing 19 surrounding the plug frame 18 so as to be in free sliding contact with an outside thereof; one light-shielding plate (shutter) 22 having a curved shape, fixed at one end portion thereof to an inner wall of the front housing 19, and configured to block light at a position in front of the ferrule 16; and a locking housing 20 configured to be fitted from the rear of the plug frame 18 as described in JP-A-2011-13606.
With the LC-type plug with a shutter 15, the light shielding plate 22 blocks a laser from the ferrule 16 to protect eyes or the like in a non-connected state, the light-shielding plate 22 comes into abutment with an opening edge portion of the plug frame 18 by a rearward movement of the front housing 19 in a connected state and is extended from a curved shape to a straight shape, and the ferrule 16 projects from an opening end of the front housing 19 moved rearward. Accordingly, the ferrule 16 on the LC type plug 15 with a shutter side and a ferrule on an LC type adapter 24 side, which is a connection counterpart (see FIGS. 6A and 6B) are connected.
However, since the light-shielding plate 22 in the LC type plug 15, which is an example of the optical connector plug with a shutter of the prior art, is brought into a state of being sandwiched between the plug frame 18 and the front housing 19 when being fitted to the LC type adapter 24 and hence is stored in a state of being subjected to a load, a center portion of the light-shielding plate 22 is deformed and protruded.
Accordingly, a retaining square hole 22c provided on the light-shielding plate 22 illustrated in FIGS. 10A and 10B may climb over a central projection 19c for locking the light-shielding plate on a bottom portion of the front housing 19 illustrated in FIGS. 11B and 11C, so that the light shielding plate 22 may come off from the front housing 19 during an opening and closing action repeated by the front housing 19.